Giving reviews on Google is very easy and can take less than a minute.
Click the green button below the gif, to go to the page where you can add a review.
Click the blue text as shown in the gif.

Click the button that says "Write a review" in the top right-hand corner.
Add rating and review in the new window.
Capterra
To add a review, you simply just click the 'Write a Review!' text, as shown below:

When you click the text, you will be forwarded to a page (the first of 3) where you can add your contact information as well as info about your usage of Actimo. If you want to save time (and have a LinkedIn-account) you can sign in with Linkedin at the top of the page.
On the 2nd page, you are asked to rate different aspects of your experience with Actimo, for example, value for money and ease of use and how likely you are to recommend it to a friend or colleague. There is also a long list of features that you can rate (not mandatory).
On the 3rd and last page, you are asked to write about pros, cons, and overall experience, and why you chose Actimo in the first place. Once this has been filled out you just have to click the submit button and the review is done.